1Field of the Invention
The present invention relates to a tyre for motor vehicles, i.e. a tyre having a high transversal curvature so as to offer an adequate contact surface with the road surface when the motor vehicle is leaning to turn a bend.
2Description of the Art
Preferably, the tyre of the present invention is intended to be used in a front wheel of motor vehicles of the “Sport Touring” type, i.e. sports motor vehicles intended to offer high performance in terms of power, comfort and mileage on motorways and streets, in cities and/or outside cities and/or off-road, with a wet or dry road surface.
“Sport Touring” motor vehicles typically have a large piston displacement (equal to or greater than 800 cm3) and/or high power (equal to or greater than 110 HP). However, on the market there are already motor vehicles having a piston displacement equal to 1400 cm3 and power equal to 155 HP.
It is known that the tyres for the front wheels of such motor vehicles must ensure high performance on any type of road surface (wet, dry, regular and/or irregular asphalt, etc.) and/or route (city streets, motorways, mountain roads with a large number of bends) and/or load conditions (just the driver, with passenger).
Such tyres must also ensure driving stability, controllability, directionality, road-holding, high mileage and regular wear.
Amongst the aforementioned characteristics, of particular importance is, in the specific case of tyres for front wheels, the water drainage. Indeed, it is essential for the tyre of the front wheel of motor vehicles to be able to ensure effective water drainage in the case of travel on a wet road surface, so that the tyre of the rear wheel, travelling in a straight line on the drained asphalt, can effectively discharge the power and the driving forces to the ground.
For this reason multiple grooves are formed on the tread band of the tyre that extends from the annular central portion of the tread band up to the opposite annular shoulder portions.
It is known how the behaviour of the tyre during travel is greatly influenced by the number, orientation, distribution and shape of such grooves, and thus by the particular pattern of the tread band.
EP 0 906 836 describes a tyre for a motor vehicle the tread band of which comprises a central region astride of an equatorial plane of the tyre and two shoulder regions arranged on axially opposite sides with respect to the central region. In the tread band a plurality of grooves are formed that extend from opposite sides with respect to the equatorial plane starting from the equatorial plane itself up to the shoulder regions and according to a direction that in the central region is substantially circumferential, in the shoulder regions is substantially transversal and in the intermediate regions progressively changes from substantially circumferential to substantially transversal proceeding from the equatorial plane towards the shoulder regions. The grooves formed on one side of the tyre with respect to the equatorial plane thereof are staggered along the circumferential direction with respect to the corresponding grooves formed on the other side of the tyre.